A U.S. State Department official said on Tuesday that Washington has no plans to change a Cold War-era law granting special immigration benefits to Cubans, despite President Barack Obama's moves toward normalized relations with the island country.

"There continues to be a large migration flow out of Cuba. It reflects the difficult economic and human rights conditions in the country," Francisco Palmieri, principal deputy assistant secretary in State's Bureau of Western Hemisphere Affairs, told a Senate subcommittee hearing.

"We have no plans to change the Cuban Adjustment Act at this time," Palmieri said.

The Cuban Adjustment Act provides Cubans with benefits granted to migrants from no other country. Once they enter the United States and ask for asylum, virtually all are granted the right to stay, can apply for work permits and, later, green cards, which convey lawful permanent residency.

Some U.S. lawmakers have been demanding a fresh look at Cuban immigration policy since the surprise December 2014 announcement from Obama and Cuban President Raul Castro that the two countries would move toward ending decades of estrangement.

They argue that most of the Cubans coming to the United States are coming for economic reasons and are not refugees from its Communist government.

Fear of an end to their benefits has fueled a surge in departures from Cuba, many via third countries, which has left large groups of Cubans stranded in Central America.

Earlier this year, thousands were airlifted from Panama and Costa Rica to northern Mexico, where they crossed the border into the United States.